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Chd|====================================================================
Chd|  QRROTA2                       source/elements/solid_2d/quad/qrrota2.F
Chd|-- called by -----------
Chd|        QFORC2                        source/elements/solid_2d/quad/qforc2.F
Chd|-- calls ---------------
Chd|====================================================================
      SUBROUTINE QRROTA2(
     1   R22,     R23,     R32,     R33,
     2   F11,     F21,     F12,     F22,
     3   T11,     T21,     T12,     T22,
     4   T13,     T23,     T14,     T24,
     5   NEL)
C-----------------------------------------------
C   I m p l i c i t   T y p e s
C-----------------------------------------------
#include      "implicit_f.inc"
C-----------------------------------------------
C   G l o b a l   P a r a m e t e r s
C-----------------------------------------------
C-----------------------------------------------
C   D u m m y   A r g u m e n t s
C-----------------------------------------------
      INTEGER, INTENT(IN) :: NEL
C     REAL
      my_real
     .   R22(*), R23(*), R32(*), R33(*),
     .   F11(*), F21(*), F12(*), F22(*),
     .   T11(*), T21(*), T12(*), T22(*),
     .   T13(*), T23(*), T14(*), T24(*)
C-----------------------------------------------
C   L o c a l   V a r i a b l e s
C-----------------------------------------------
      INTEGER I
C     REAL
      my_real
     .   Y,Z
C-----------------------------------------------
C     X=RX' <=> X'=t(R)X chgt de base.
      DO I=1,NEL
        Y=R22(I)*F11(I)+R32(I)*F21(I)
        Z=R23(I)*F11(I)+R33(I)*F21(I)
        F11(I)=Y
        F21(I)=Z
      END DO
      DO I=1,NEL
        Y=R22(I)*F12(I)+R32(I)*F22(I)
        Z=R23(I)*F12(I)+R33(I)*F22(I)
        F12(I)=Y
        F22(I)=Z
      END DO
      DO I=1,NEL
        Y=R22(I)*T11(I)+R32(I)*T21(I)
        Z=R23(I)*T11(I)+R33(I)*T21(I)
        T11(I)=Y
        T21(I)=Z
      END DO
      DO I=1,NEL
        Y=R22(I)*T12(I)+R32(I)*T22(I)
        Z=R23(I)*T12(I)+R33(I)*T22(I)
        T12(I)=Y
        T22(I)=Z
      END DO
      DO I=1,NEL
        Y=R22(I)*T13(I)+R32(I)*T23(I)
        Z=R23(I)*T13(I)+R33(I)*T23(I)
        T13(I)=Y
        T23(I)=Z
      END DO
      DO I=1,NEL
        Y=R22(I)*T14(I)+R32(I)*T24(I)
        Z=R23(I)*T14(I)+R33(I)*T24(I)
        T14(I)=Y
        T24(I)=Z
      END DO
c~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      RETURN
      END
